I use Pandora and I'm able to maintain genre-specific stations pretty well. Sometimes it will try to mix something new in but I just dislike that song and it happily keeps playing the genre(s) that I chose for that channel.
I don't know about Pandora, but I've always been cautious to use "dislike" in that way, because I don't know the scope. There's a difference between "I don't want to ever hear this" vs "I don't want to hear it on this station". I use it for the former but not the latter.
My experience has been that dislikes are station specific. I regularly dislike songs on channels in order to shape the genre, even if I actively listen to that song on other stations. Pandora's whole identity revolves around stations, so it would be weird if dislikes were global.
I've found the pandora community post below that seems to confirm it, though I'm not sure whether the community admin answering the question is actually a pandora employee or not.
Yeah, the opaqueness of your actions in Pandora and in other streaming services is always annoying.
Likewise, Pandora allows you to create a station with multiple seeds, or (is it the same?) like songs within a station.
I used to use that, and then I felt like it was narrowing the breadth of the station. I realized that in my mental model I wanted it to be a station of Artist A plus Artist B, so a more expansive station, but Pandora seemed to be treating it as "Artist A ∩ Artist B," i.e. just the small intersection.
